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[grc]

The shake at idle you feel on the new 09 is likely due to the rear cylinder cut off feature.  In an effort to combat heat, HD sacrificed a little vibration.  Trust me, your woman will love it!

Actually, the shake you see and feel at idle is due to the poor primary balance and uneven firing cadence of a 45° V-twin.  If the rubber mounts were hard enough to stop the shake, they would be too hard to isolate the vibrations at higher speeds.  When the rear cylinder deactivation kicks in at high temps, I would expect it to run even rougher with only one big bang per 720° of engine rotation.

Any vibration reduction system is a compromise.  Rubber mounts work best in certain rpm ranges but not in all, and the same is true of the counterbalance systems.  Mrmagloo's idea of combining the two systems definitely has merit, since each could be tuned for best effect where the other isn't very effective.  I still think we'll never see it due to the cost difference.

Jerry

[mrmagloo]

Thanks GRC - That was exactly the idea. I would defintely not want to use the same rubber mounts and make the thing feel like you're driving a Prius. Essentially, it would be more like swapping out the hard mounts on a counter balanced B in a softail with relatively stiff urethane mounts. You would get the best of both worlds in that the engine would stay relatively stable at idle and low rpm's, but at speed, you'd get rid of the hard mount buzz at some higher rpm's. You would absolutely still feel the V-Twin lope, and the 'good vibrations' - the only thing different is the handle bars and the entire front fork won't be bouncing back and forth at the light. If you wanted, you could even tune it a bit with slightly lower or higher durameter urethane. The bottom-line is, in volume it wouldn't cost the MOCO much to run counter balanced motors across the board. The efficiencies through standardizing across the lines would present some real savings to boot. I dunno, but never quite understood why they ever stuck with unbalanced this long.

[OILCAN1]

All  that bouncing and jumping at idle is what makes a Harley a Harley, I mean come on aint it cool when a soccer mom pulls up next to you at a stoplight and her little rugrats stare and say "Look mommy I think the mirror is gona fall off"  Hee Hee

[SPIDERMAN]

All  that bouncing and jumping at idle is what makes a Harley a Harley, I mean come on aint it cool when a soccer mom pulls up next to you at a stoplight and her little rugrats stare and say "Look mommy I think the mirror is gona fall off"  Hee Hee

No that only happens when you're sitting at a light next to a snotty RUB on a full dress Beemer with a $1,000 helmet and a $3,000 riding suit

B B

[OILCAN1]

Yeah your right or maybe the snot nosed punk on the crotch rocket wearing shorts and flip flops.

[Steve_G]

magloo,
          When H-D came out with the first B motor bikes, they actually had a problem with the lack of vibration having something to do with the compensator sprokets or something. I wish I could remember what the issue was. Anyway, a B motor with rubber mounts would indeed be smooth as glass and for a lot of us would not feel at all like a Harley-Davidson.

Just my $0.02

B B

When I lived in Sioux Falls I asked the Lonnie (the L in J&L HD of Sioux Falls) why they didn't use a counter balanced motor with rubber mounts.  He said the MoCo tried it and decided not to go that way because it was smoother than a Goldwing.  Just like you said B B it "would not feel at all like a Harley-Davidson".

[mrmagloo]

When I lived in Sioux Falls I asked the Lonnie (the L in J&L HD of Sioux Falls) why they didn't use a counter balanced motor with rubber mounts.  He said the MoCo tried it and decided not to go that way because it was smoother than a Goldwing.  Just like you said B B it "would not feel at all like a Harley-Davidson".

Precisely why you would want to go with harder mounts. Again, not solid, but definitely firmer than the current rubber. The beautiful thing about urethane is you can blend it to virtually any durameter hardness from almost silicon goshy to almost hard as steel. so you can essentially tune it to your preference. Could even do multi-durameter layers, to create a progressive rate mount. It's pretty remarkable stuff. I've been out of the plastics industry for 20 something years so I'm talking about ancient technology.